1. Field
Apparatuses and methods consistent with exemplary embodiments relate to a magnetic resonance imaging (MRI) apparatuses and methods configured to generate an MR image by detecting a nuclear magnetic resonance (NMR) signal from a subject, and a control method thereof.
2. Description of the Related Art
An MRI apparatus generates a medical image of a subject by using a magnetic field. However, a great amount of noise is generated while magnetic field gradients are being formed, during an MRI imaging of the subject. Methods of cancelling the noise include a manual noise cancelling method and an active noise cancelling method. The manual noise cancelling method uses insulation and absorption, as for example, covering the ears of an imaged subject with a cup or a can. The active noise cancelling method includes a feedback technology and a feed-forward technology. However, with respect to the MRI apparatus, in the related art, the feedback technology is used together with the manual noise cancelling method.
For example, the noise cancelling method of the related MRI apparatus uses a can that covers the ears of a subject, and by detecting the noise inside the can, the noise is cancelled by creating a null in the inside chamber of the can. However, when imaging a patient's head, a head coil is mounted on the patient's head, and the can needs to have a double structure. Moreover, sometimes the can cannot be used due to the size of the patient's head, and the noise reaching the subject is not being cancelled.
Further, in the related art active noise cancelling method, the sound wave configured to cancel the noise is output without considering the position of the head of the subject, i.e., the positions of the ears of the subject. Accordingly, the noise being reached at the subject may not be effectively cancelled. Another related art method provides an additional headset composed of a microphone and a speaker to be mounted on the head for noise cancellation. Such methodology is cumbersome and inconvenient for the patient.